Method for revamping fixed-bed catalytic reformers

ABSTRACT

A fixed-bed catalytic reformer unit is converted to moving bed reactor/cyclic regenerator operation by re-using the fixed bed reactors of the original unit as regenerator vessels operated in cyclic regeneration mode in a new catalyst regeneration section. A flow connection, suitably a liftpipe, is provided to convey spent catalyst from the spent catalyst outlet of a new moving bed reactor section to the converted regenerator section, together with a flow connection for regenerated catalyst from the regenerator section to the regenerated catalyst inlet of the new moving bed reactor section. A flow control distributor directs spent catalyst sequentially to each of the regenerator vessels to carry out the regeneration with regeneration gas. Each regenerator vessel is cycled through a fill, regeneration, discharge sequence to maintain a continuous flow of catalyst to and from the reactor section.

CROSS REFERENCE TO RELATED APPLICATION

This application relates to a method of converting or revamping fixedbed catalyic reformers to moving bed reactor operation and, as such, isrelated to US 2004/0129605 A1, published Jul. 8, 2004, which described adifferent conversion scheme.

This application claims the benefit of U.S. Ser. No. 60/564,133 filedApr. 21, 2004.

FIELD OF THE INVENTION

The invention relates generally to catalytic reformers. Moreparticularly, the invention relates to an improved method for convertingor revamping high pressure, fixed-bed catalytic reformers to catalyticreformers with continuous, moving-bed reactors.

BACKGROUND OF THE INVENTION

Catalytic reforming is an established petroleum refinery process. It isused for improving the octane quality of hydrocarbon feeds. Generally,reforming refers to the total effect of molecular changes on ahydrocarbon feed, produced by a number of reactions. Typical reformingreactions include dehydrogenation of cyclohexanes, dehydroisomerizationof alkylcyclopentanes, dehydrocyclization of paraffins and olefins,isomerization of substituted aromatics, and hydrocracking of paraffins.Typical reforming catalysts are multifunctional catalysts having ahydrogenation-dehydrogenation component dispersed on a porous, inorganicoxide support. The support may typically also contain an acidfunctionality needed to mediate the reforming reactions.

Reforming reactions are both endothermic and exothermic. Endothermicreactions are typically predominant in the early stages of reformingwhile exothermic reactions predominate in the later reaction stagesalthough the process as a whole is markedly endothermic. A reformingunit typically comprises a plurality of serially connected reactors withfurnaces for supplying additional heat to the reaction stream as itpasses from one reactor to the next in order to compensate for the heattaken up in the overall endothermic character of the process.Conventionally, reforming processes have been operated assemi-regenerative or cyclic processes using fixed bed reactors orcontinuous processes such as UOP CCR Platforming™ (Continuous CatalyticRegeneration Platforming™) using moving bed reactors.

Proposals have been made for combining fixed and moving bed reactorswith the regeneration mode appropriate to the reactor types used in thehybrid configuration, so that the fixed bed reactors have retained thefixed bed type regeneration, usually semiregenerative, and the movingbed reactors in the unit have retained the dedicated moving bedregenerator. Units of this hybrid type are disclosed, for example, inU.S. Pat. No. 5,190,638; U.S. Pat. No. 5,190,639; U.S. Pat. No.5,196,110; U.S. Pat. No. 5,211,838; U.S. Pat. No. 5,221,463; U.S. Pat.No. 5,354,451; U.S. Pat. No. 5,368,720 and U.S. Pat. No. 5,417,843. Theunit described in U.S. Pat. No. 5,417,843 uses two trains of fixed bedreactors with each train having a final moving bed reactor at the endand the moving bed reactors sharing a moving bed regenerator. The unitshown in U.S. Pat. No. 5,190,639 uses two trains of fixed bed unitsfeeding into a shared moving bed reactor with its own dedicated, fullyintegrated regenerator. Similar hybrid reforming units usingcombinations of fixed bed and moving bed reactors are described in NPRAPaper No. AM-96-50 “IFP Solutions for Revamping Catalytic ReformingUnits” (1996 NPRA Annual Meeting, 17-19 Mar. 1996). U.S. Pat. No.4,498,973 describes a moving bed reforming unit in which two moving bedreactor stacks share a common regenerator. UOP has recently announcedits CycleX™ Process for increased hydrogen production from a fixed bedreforming unit by the addition of a circulating catalyst reactor as thefinal reactor in the reactor sequence. This reactor is provided with itsown heater and regenerator as an expansion of existing assets ratherthan as a substitution of them: NPRA Paper AM-03-93.

In semiregenerative reforming, the entire reforming process unit isoperated by gradually and progressively increasing the temperature tocompensate for deactivation of the catalyst caused by coke deposition,until finally the entire unit is shut-down for regeneration andreactivation of the catalyst which is carried out with the catalystremaining in the reactor cases. In cyclic reforming, the reactors areindividually isolated by various piping arrangements. The catalyst isregenerated and then reactivated while the other reactors of the seriesremain on line. A “swing reactor” temporarily replaces the reactor whichis removed from the series for regeneration and reactivation of thecatalyst, which is then put back in the series. In continuous reforming,the reactors are moving-bed reactors with continuous or intermittentaddition and withdrawal of catalyst through which the catalyst movesprogressively before it is passed to a regeneration zone forregeneration and rejuvenation before being returned once again to thereactor. In the regenerator, at least a portion of the deposited coke isburned off and the regenerated catalyst is recycled to the reactor tocontinue the cycle. Commercial continuous reforming units may have thereactors arranged in a side-by-side or in a stacked configuration.Because the continuous mode of operation with its frequent regenerationcan tolerate a higher degree of coke lay-down on the catalyst, it ispossible to operate continuous units at lower pressures than thosenormally used with semi-regenerative and cyclic units in which it isimportant or at least desirable to extend catalyst life betweensuccessive regenerations.

Environmental concerns have driven the removal of lead from the gasolinepool and the introduction of premium grade, higher octane, lead-freegasoline in Europe and the United States. In response, petroleum refmershave changed the manner in which refinery units are run to meet theconcomitant demand for higher octane, lead-free gasoline. Catalyticreforming units produce a major portion of the refinery gasoline pooland for this reason, improved reforming methods and units are needed forproducing lead-free fuel products with adequate octane ratings.Reforming can also be an attractive source of hydrogen in the refinery,especially when the sulfur level of fuels must be reduced to meetgovernment regulations.

Semiregenerative reforming units may be converted to continuousmoving-bed units to take advantage of the improved yield of higheroctane reformate and hydrogen associated with continuous operation butthe conversions which have so far been considered are essentially entireunit replacements which require replacement of all existing vessels andmost of the ancillary equipment as well as installation of an integratedcatalyst regenerator which is one of the most costly items in theconversion. The cost of the regenerator can be as much as about 80percent of the total cost required for the conversion, making thisoption less attractive when the original fixed bed units are stillcapable of service.

US 2004/0129605 A1 describes an economically attractive method forconverting fixed bed catalytic reforming units to continuous reactoroperation while reducing the costs associated with continuousregeneration. In this conversion scheme, a fixed-bed catalytic reformerwith at least one fixed-bed is converted semiregenerative to amoving-bed catalytic reformer reactor which allows continuous orintermittent addition of fresh or regenerated catalyst through suitablefeed facilities to its catalyst inlet. Provision is made for continuousor intermittent removal of spent catalyst from the catalyst outlet ofthe reactor by way of spent catalyst recovery facilities for collectingthe spent catalyst, storing it temporarily, and transferring it to acatalyst regeneration facility. The moving-bed reactor, the catalystfeeding facilities and the catalyst recovery facilities are operativelyconnected between themselves and to the existing facilities (piping,ancillary equipment) of the fixed-bed unit that do not requirereplacement.

SUMMARY OF THE INVENTION

The present invention relates to a scheme for converting fixed-bed,catalytic reformer units to units with moving bed reactors. It differsfrom the scheme described in US 2004/0129605 A1 in that it makes use ofexisting reactor vessels; in the present case, these vessels are placedinto new service, this time for catalyst regeneration. Because thisconversion scheme requires only new reactors, it avoids the majorexpense connected with the provision of a moving bed regenerator and sopresents an economically favorable case for conversion to moving bedreactor operation. The costs of conversion associated with the presentconversion technique will be significantly less than conversions inwhich both the reactors and the regenerators are converted to moving bedoperation because the present conversion technique makes use of existingfacilities in addition to making new use of the reactor vessels while,at the same time, not requiring dedicated onsite continuous catalystregeneration facilities. One advantage of the present conversion schemeis that the full advantages of moving bed reactor operation are securedwith the reactors operated at the lower pressures characteristic ofcontinuous operation so as to improve reformate quality and yield.

According to the present invention, a fixed-bed catalytic reformer unitis converted to moving bed reactor/cyclic regenerator operation byre-using the fixed bed reactors of the original unit as regeneratorvessels operated in cyclic regeneration mode in a converted regenerationsection. A flow connection, suitably a liftpipe, is provided to conveyspent catalyst from the spent catalyst outlet of a new moving bedreactor section to the converted regenerator section, together with aflow connection for regenerated catalyst from the regenerator section tothe catalyst inlet of the new moving bed reactor section. A flow controldistributor directs spent catalyst sequentially to each of theregenerator vessels to carry out the regeneration with regeneration gas.Each regenerator vessel is cycled through a fill, regeneration,discharge sequence to maintain a continuous flow of catalyst to and fromthe reactor section.

In the present conversion technique and its allied operational mode, afixed bed reformer unit with a plurality of reactor vessels is convertedto a continuous reformer unit with a moving bed reactor section and amulti-vessel catalyst regeneration section operating in cyclic fashion,using the former reactor vessels for regeneration. The former reactorvessels are re-used for regeneration in the new, cyclical operation,typically on a three-vessel fill/regenerate/discharge cycle, in whichone vessel receives spent catalyst, while another is in the regenerationcycle and another is discharging regenerated catalyst for recycle to thereactor stack. This conversion scheme is particularly well adapted tothe conversion of cyclic reforming units where the regeneration circuit(compressor, furnace, chemical injection facilities, valving, piping andmanifolding) can be used with advantage for the purposes of cyclicregeneration in the converted unit. The conversion scheme may, however,be also applied to existing semi-regenerative units although here withthe marginal economic disadvantage of having to provide a newregeneration circuit.

THE DRAWING

FIG. 1 shows a continuous moving-bed reforming process built from anexisting cyclic reformer unit.

DETAILED DESCRIPTION

The present invention provides a substantially lower cost option forrefiners to make significant improvements to the performance and servicefactor of existing fixed-bed reformer units. Non-continuous (orfixed-bed) catalytic reformers which can be subjected to the presentconversion scheme could be semi-regenerative catalytic reformers orswing-reactor (also referred to as cyclic regeneration) reformers orhybrid systems (with both fixed and moving bed sections), all of whichare known.

The present conversion scheme is best adapted to the conversion ofcyclic reformer units because the required catalyst regenerationequipment will already be in place and can be applied directly to thenew service: the compressors, furnace, chemical injection facilities aswell as piping, valving and manifolding can be used without substantialmodification to the mode of cyclic regeneration used in the convertedunit. Cyclic, fixed-bed reformers have been well-known. In units of thistype, a plurality of reactors are used, typically from three to five,with one reactor being the so-called “swing” reactor. The actualreforming is carried out in the remaining reactors according to thenormal reforming reactor sequence while the catalyst in the “swing”reactor is being regenerated by the flow of regeneration gas through thecatalyst. In the normal operation sequence, the reactor with thecatalyst which has aged the most, is withdrawn from the reformingsequence (taken “off-oil”): after the oil feed is cut off, the catalystin the vessel is subjected to regeneration sequence typically with apurge of residual hydrocarbons (nitrogen purge), oxidative regenerationto burn off the accumulated coke on the catalyst, halogenativerejuvenation (usually a chlorination treatment), followed by a purge ofoxides and residual occluded gases and a final hydrogen reduction, afterwhich the reactor is returned on line by bringing it “on-oil” againwhile another vessel is taken off-oil for regeneration. Normally, theswing time has been about three to five days. For convenience, the term“regeneration gas” is used here to comprehend the various gases used inthe regeneration sequence referred to above, including the heated purgegas (usually nitrogen), oxidative gas for coke burn-off, halogenationgas for rejuvenation, purge gas, hydrogen for reduction and, if requiredby the catalyst chemistry, the pre-sulfiding gas treatment.

It is not essential, however, that the fixed bed unit being subjected toconversion should be a cyclic unit; conversion of semi-regenerativeunits is feasible since these units will also provide multiple reactorvessels as assets for conversion to cyclic regeneration use. This typeof conversion, however, will be accompanied by the necessity to provideadditional ancillary equipment for the regeneration circuit includingcompressors, furnace, piping, valving and manifolding. Semi-regenerativeunits typically contain one or more fixed-bed reactors operating inseries with inter-bed heaters to maintain operating severity as thecatalyst deactivates by increasing the reaction temperature and tomaintain the desired temperature profile across the unit as the ratio ofendothermic to exothermic reactions increases in successive reactors.Eventually, a semi-regenerative unit is shut down for catalystregeneration and reactivation in its original mode of operation. Afterconversion according to the present scheme, however, the reactor vesselsare used as cyclically-operated regenerator vessels for a continuous,moving bed reactor stack.

The fixed-bed reformer unit is converted to a moving-bed reformerreactor that allows continuous addition of freshly regenerated catalystto an inlet of the reactor and continuous removal of spent catalyst froman outlet of the reactor. Although the regeneration is carried out in acyclical operation with the spent catalyst passing successively betweenthe new moving bed reactor section the former reactor vessels (nowfunctioning as regenerator vessels), the provision of suitable spent andregenerated catalyst receivers (along with an adequate catalystinventory) will allow for continuous catalyst flow to the reactorsection.

The conversion of a fixed bed (semi-regenerative or cyclic) reformerunit to operation with moving-bed reactors comprehends the replacementof the fixed bed reactors by a moving bed reactor section. Normally,since moving bed operation provides optimal reforming performance, allthe former fixed-bed reactors will be replaced by the moving bed reactorsection but, if for some reason, it is desired to have a hybrid typeunit with a fixed/moving bed configuration, some of the fixed bedreactors may be retained in the hybrid service. The reactor section willhave, as is conventional, a number of moving bed reactors connected insequence for reformer feed flow and for catalyst flow from one reactorto the next. The moving bed reactors may be disposed in a side-by-sideor stacked arrangement, depending on site requirements although thestacked configuration provides for ready catalyst transfer betweensuccessive reactors by gravitational flow. The conversion does requireaddition of catalyst transfer facilities between the new moving bedreactor(s) and the converted, fixed bed vessels now used in the cyclicregeneration sequence but much ancillary equipment of the fixed bed unitcan be retained and put to new use, especially, as noted above, thepiping associated with cyclic units. Feed (oil) arrangements will needto be modified as required to suit the layout of the converted unit andits operational requirements.

As mentioned above, a former cyclic reforming unit has the necessarycatalyst regeneration circuit ready for use in the new application.Since the equipment in this circuit is adapted to regenerating thecatalyst in place in the reactor vessels, with the appropriate sequenceof regeneration gas, this same equipment can be directly applied to thecyclic regeneration mode which is used in the converted unit. If,however, a former semi-regenerative reformer is converted to the newmode of operation, a catalyst regeneration circuit with its associatedcompressors, furnace, chemical injection facilities as well as valving,piping and manifolding will need to be supplied and connectedappropriately to the former reactor vessels. The general form of thisequipment as well as its service requirements and manner of use willfollow those of conventional cyclic units and, being well known, willnot be described in detail here.

FIG. 1, given for example only, shows a continuous catalytic moving-bedreforming process unit which has been converted from a former cyclicreformer. The converted unit is composed of a moving bed reactor section10 which is integrated with a regeneration section 11 with threeregeneration vessels, 12, 13, 14 which are the former reactors of acyclic reformer; the former reactors and regeneration system areenclosed by dashed line 15. The figure concerns itself only with thecatalyst handling circuit, omitting details of the hydrocarbon feed andrecovery equipment as well as furnaces and other ancillary items whichare conventional for the reactor stack.

In operation, the reactor section is operated in the conventional wayfor a stacked reactor configuration with hydrocarbon feed beingintroduced into the reactor at the top of the stack and effluent removedfrom the last reactor at the bottom of the stack. Catalyst moves downthrough the reactors of the stack progressively from bed to bed,entering the catalyst inlet 10A at the top of the stack and leaving atthe spent catalyst outlet 10B at the bottom of the last reactor in thestack (here, the fourth reactor). The spent catalyst passes down fromthe catalyst outlet through a spent catalyst removal line 20, lockvalves 21 to catalyst lift pot or lift entrainer 23 in which the spentcatalyst is entrained by lift gas which elevates the catalyst upliftpipe 24. The lift gas, supplied through conduit 25 under the controlof differential pressure/flow controller 27, is suitably booster gas,that is, gas from the compressor of the recycle gas circuit, comprisingmainly hydrogen with minor quantities of hydrocarbons, which is heatedto approximately 350° C. (about 700° F.) in effluent heat exchanger 28.

After being conveyed upwards in liftpipe 24, the spent catalyst passesinto disengager 30 and then into surge vessel/elutriator 31 in which thelift gas is separated and fines removed. The fines are recovered in thefmes recovery section with filters 32A and 32B and fines collector 33;gas passes out to the gas circuit through line 34.

From the surge vessel/elutriator 31, the spent catalyst passes throughlock 35 to flow control hopper/distributor 36. Flow controlhopper/distributor 36 enables catalyst to be distributed to each ofregenerator vessels 12, 13 or 14. The catalyst passes from flow controlhopper/distributor in lines 37, 38, 39, through locks 40A, 40B, 40C anddouble block and bleed valves 41A, 41B, 41C, to regenerator vessels 12,13 and 14. Block gas supply to the double and bleed valves is providedin conventional manner as shown with gas supplies, suitably of refineryfuel gas through lines 42A, 42B, 42C. Similar locks 43A, 43B, 43C anddouble block and bleed valves 44A, 44B, 44C, are provided at thecatalyst outlets of vessels 12, 13 and 14. Block gas supply to thedouble and bleed valves on the outlets is provided in conventionalmanner as shown with gas supplies, suitably of refinery fuel gas throughlines 45A, 45B, 45C. Make up catalyst can be admitted when requiredthrough valve 71 from catalyst drum 70.

Regenerator vessels 12, 13, 14 are the previously used axial reactorswhich were made redundant when they were replaced by the moving bedcontinuous reactors. Typically, at any point in time, one of the threeregeneration vessels is in the “Spent Catalyst Fill” mode, one is in the“Regeneration” mode, and the remaining one is in the “RegeneratedCatalyst Discharge” mode. The double block and bleed motor operatedvalves on the regenerator flow allow the reactors to be isolated fromregeneration gas flow when they are in the “Spent Catalyst Fill” mode orthe “Regenerated Catalyst Discharge” mode.

“Spent Catalyst Fill” Mode

When a regeneration vessel is filling it is isolated from regenerationgas flow by double block and bleed valve arrangements 41A, 41B, 41C atthe inlets and 44A, 44B, 44C at the outlets of the vessels. Catalyst isflowing from the flow control hopper/distributor 36 into the selectedregenerator vessel through the spent catalyst fill line that protrudesthrough the regeneration flow inlet spool piece 12A, 13A, 14A of theselected vessel. The regenerated catalyst emptying line that protrudesthrough each regeneration flow outlet spool piece 12B, 13B, 14B isclosed.

“Regeneration” Mode

During catalyst regeneration in one of the three regeneration vessels,the appropriate spent catalyst filling line 37, 38, 39 and thecorresponding regenerated catalyst emptying line is closed. Regenerationgas flows into the regenerator vessel through the respectiveregeneration gas inlet spool piece 12A, 13A, 14A, and out of the vesselthrough the regeneration gas outlet spool piece 12B, 13B, 14B asindicated by gas flow arrows (not numbered). Regeneration off-gases aresent to the scrubber in the conventional way. The catalyst lines areisolated from the regeneration gas with the double block and bleed valvearrangements 41A, 41B, 41C, 44A, 44B, 44C on the inlet and outlet sidesrespectively. The regeneration circuit that was used in the cyclic unitbefore the conversion provides the facilities required for compression,furnace, heat exchange, and regeneration gas and chemical injectionduring the regeneration. These facilities will be flexible enough tomeet the regeneration procedure requirements for known reformingcatalysts. The regeneration sequence with its purge, coke burn-off,halogenation, purge, reduction and, if desired, pre-sulfiding, can becarried out according to conventional practice as dictated byoperational requirements and catalyst chemistry in a manner comparableto that used in conventional cyclic units.

“Regenerated Catalyst Discharge” Mode

When a regenerator vessel is being emptied, it is isolated fromregeneration gas flow by double block and bleed valve arrangements atthe vapor inlet and outlet of the reactor. Catalyst is discharged fromthe regenerator vessel through the appropriate regenerated catalystdischarge line 50, 51, 52 that protrudes through the vapor outlet spoolpiece 12B, 13B, 14B of the respective vessel and passes into a liftentrainer 60 beneath the regenerator vessel group. Recycle gas suppliedthrough line 61 under control of differential pressure/flow controller62 is used to entrain the regenerated catalyst in lift entrainer 60 andelevate it through liftpipe 63 up to the catalyst disengaging vessel 64located above the reduction zone 10B at the top of moving bed reactor10. The spent catalyst filling line that protrudes through theregeneration flow inlet spool piece 12A, 13A, 14A, respectively, isclosed.

Cycle Control

The regeneration cycle operation is under the control of a sequentialcycle controller (not shown) and associated control equipment, all ofwhich is of conventional type. The controller acts to maintain the flowof spent catalyst from the flow control hopper/distributor to theselected regeneration vessel which is in the “Spent Catalyst Filling”mode while, at the same time regulating the valving to the other vesselsto put the regenerator vessel in the “Regeneration” mode into theregeneration cycle and the third vessel into the “Regenerated CatalystEmptying” mode. This involves actuation of the catalyst flow valves andthe gas flow valves and blocks to obtain the required actions, all ofwhich can be carried out by conventional controllers, control circuits,actuators and related equipment. The regeneration cycle for the catalystwill be determined by catalyst and operational requirements and may beunder the control of the main cycle controller or a regenerationsub-controller operating under the overall control of the maincontroller. The regeneration cycle controller of either type will needmainly to control the flow of regeneration gas to the vessel which is inthe “Regeneration” mode. Typically, this will include a regeneration gassequence comprising a hydrocarbon purge (hot nitrogen), coke burn (hotoxygen-containing gas), oxy-chlorination, oxides purge (hot nitrogen),and reduction (hydrogen). The reduction step may, however, be carriedout at the inlet of the reactor section, for example, above the firstreactor in a stacked configuration and, if so provided, may be omittedfrom the sequence carried out in the regeneration section. Othervariations in the sequence will be dictated by catalyst requirements andcan be accommodated by conventional modifications to the cycle controland appropriate provision in the regeneration system.

Unit Layout

Because this is essentially a conversion or revamp scheme, the finalunit layout will normally be determined to a large degree by specificsite requirements. So, the configuration and location of the reactorsection may well be constrained by the site as well as the relativelocation of the regeneration section; normally, cost considerations willpreclude relocation of the old fixed bed reactors to a new location,especially if the old unit were a cyclic unit with the associated pipingin the regeneration circuit. This will often require appropriate sitingof the new moving bed reactor section. With a stacked reactorconfiguration, the side-by-side configuration typical of old cyclic andsemi-regenerative units will require the use of lift systems for thespent and regenerated catalyst flows, as described above but this is byno means inherent in the character of the conversion; if alternativearrangements are more suitable, resort may be made to them as necessaryor convenient.

Reforming Catalyst

Any typical reforming catalyst suitable for moving bed operation may beused, consistent with the equipment limitations and feed and operationalrequirements. Suitable catalysts include those comprising one or moreGroup VIII noble metals on a refractory support. The catalyst willcontain a hydrogenation-dehydrogenation function (hydrogen transfer) andan acid function. Examples include catalysts comprising platinum, tin,rhenium, iridium, tin or combinations of these metals. A preferredsupport includes substantially spherical alumina support particles. Apreferred catalyst comprises platinum, platinum and tin, or platinum andrhenium on substantially spherical alumina support particles. Sphericalparticles are preferred for movement through the moving bed reactors andother equipment with minimal attrition.

Reforming Catalyst Regeneration

A typical regeneration procedure includes a hydrocarbon purge, cokeburn, halogenqtion (usually oxy-chlorination), oxides purge, andreduction procedure. However, depending on the type of catalyst it mayalso include presulfiding as part of the regeneration procedure. Theoxy-chlorination procedure may vary significantly. At a minimum it mayinclude the addition of a chloride containing agent such as Cl₂,HCl, ora pumpable organic chloride after the coke burn to replace the chloridelost during the coke burn. However, it may also include a continuousaddition of a chloride agent during the coke burn. It may also includeover-chlorination after the coke burn followed by a chlorideequilibration step after the platinum metal has been thoroughlyredispersed. The actual regeneration procedure might include anycombination of these chlorination techniques.

1. A method for the conversion of a fixed bed catalytic reformer unithaving at least one fixed-bed catalytic reforming reactor to moving bedreactor/cyclic regenerator operation, the method comprising: providing amoving bed, continuous reforming reactor section for carrying outcatalytic reforming reactions on a reformer feed; converting at leastone fixed bed reforming reactor of the fixed-bed catalytic reformer unitto a catalyst regenerator vessel in a catalyst regeneration section;providing a flow connection for spent catalyst from a spent catalystoutlet of the moving bed reactor section to the catalyst regeneratorvessel and providing a flow connection for regenerated catalyst from aregenerated catalyst outlet of the catalyst regenerator vessel to aregenerated catalyst inlet of the moving bed reactor section.
 2. Amethod according to claim 1 in which the fixed-bed catalytic reformerunit has a plurality of fixed-bed catalytic reforming reactors which areconverted to a plurality of cyclic operation catalyst regeneratorvessels.
 3. A method according to claim 2 which includes providing (i) aflow connection for spent catalyst from the spent catalyst outlet of themoving bed reactor section to one of the catalyst regenerator vesselsand (ii) a flow connection for regenerated catalyst from the regeneratedcatalyst outlet of one of the catalyst regenerator vessels to theregenerated catalyst inlet of the moving bed reactor.
 4. A methodaccording to claim 3 in which the flow connection for the spent catalystfrom the spent catalyst outlet of the moving bed reactor section isconnected at the end remote from the reactor section to a spent catalystflow distributor for selectively directing spent catalyst to one of theplurality of catalyst regenerator vessels.
 5. A method according toclaim 3 in which the flow connection for the regenerated catalyst fromthe catalyst regenerator vessel is connected at the end remote from thecatalyst regenerator vessel to a regenerated catalyst collector fordirecting regenerated catalyst to the catalyst inlet of the moving bedreactor section.
 6. A method according to claim 4 in which eachregeneration vessel has an inlet and an outlet for reforming catalystregeneration gas.
 7. A method according to claim 1 in which the movingbed, continuous reforming reactor section comprises a plurality ofreforming reactors in a vertically stacked configuration and thecatalyst regeneration section comprises a plurality of catalystregeneration vessels converted from the fixed bed reactors of the fixedbed reforming unit.
 8. A method according to claim 7 in which the spentcatalyst outlet of the moving bed reactor section is connected for spentcatalyst flow to a spent catalyst lift engager which has a spentcatalyst outlet connected for spent catalyst flow to a liftpipe toconvey spent catalyst to a spent catalyst flow distributor for directingspent catalyst to one of the plurality of catalyst regenerator vessels.9. A method according to claim 8 in which each of the plurality ofcatalyst regenerator vessels is connected for regenerated catalyst flowto a regenerated catalyst lift engager which has an outlet forregenerated catalyst flow to a liftpipe to convey regenerated catalystto the catalyst inlet of the moving bed reactor section.
 10. A methodaccording to claim 9 which includes means for selectively directingregenerated catalyst flow from each of the plurality of catalystregenerator vessels in sequence to the regenerated catalyst liftengager.
 11. A method for the conversion of a fixed-bed catalyticreformer unit having a plurality of fixed bed catalytic reformingreactors to moving bed reactor/cyclic regenerator operation and for theoperation of the converted unit, the method comprising: providing afixed bed catalytic reforming unit having a plurality of fixed bedreforming reactors in which catalytic reforming reactions on a reformerfeed are carried out, providing a moving bed, continuous reformingreactor section for carrying out catalytic reforming reactions on areformer feed; converting a plurality of the fixed bed reformingreactors of the fixed-bed catalytic reformer unit to catalystregenerator vessels in a catalyst regeneration section which isconnected for spent and regenerated catalyst flow between the moving bedreactor section and the catalyst regeneration section; providing a flowconnection for spent catalyst from a spent catalyst outlet of the movingbed reforming reactor section to each catalyst regenerator vessel andproviding a flow connection for regenerated catalyst from a regeneratedcatalyst outlet of each catalyst regenerator vessel to the regeneratedcatalyst inlet of the moving bed reactor section, providing a flowcontroller for selectively directing reforming catalyst regeneration gasto each catalyst regeneration vessel reforming a reformer feed in themoving bed rector section, removing spent reforming catalyst from thespent catalyst outlet of the moving bed reactor section, passing thespent reforming catalyst removed from the catalyst outlet of the movingbed reactor section to a catalyst regeneration vessel in the catalystregeneration section regenerating the spent reforming catalyst in thecatalyst regeneration vessel by directing reforming catalystregeneration gas through the catalyst in the regeneration vessel,withdrawing regenerated reforming catalyst from the regeneration vesselwhen regeneration is complete, and returning the regenerated reformingcatalyst to the catalyst inlet of the reforming reactor section.
 12. Amethod according to claim 11 in which the fixed-bed catalytic reformerunit includes a plurality of fixed bed reforming reactors each of whichis converted to a catalyst regenerator vessel in the catalystregeneration section, each catalyst regeneration vessel having (i) aspent catalyst inlet connectable for spent catalyst flow to the spentcatalyst outlet of the moving bed reactor section and (ii) a regeneratedcatalyst outlet connectable for regenerated catalyst flow to thecatalyst inlet of the moving bed reactor section.
 13. A method accordingto claim 12 in which the inlets of the catalyst regenerator vessels areeach sequentially connected for spent catalyst flow between the spentcatalyst outlet of the moving bed reactor section and the spent catalystinlet of the regenerator vessel to admit spent catalyst to theregenerator vessel in sequence for regeneration.
 14. A method accordingto claim 13 in which each catalyst regenerator vessel sequentially;first, receives spent catalyst from the spent catalyst outlet of themoving bed reactor section; second, receives reforming catalystregeneration gas to regenerate the spent reforming catalyst in theregeneration vessel; third, discharges regenerated catalyst for returnto the catalyst inlet of the moving bed reactor section.
 15. A methodaccording to claim 14 in which each of the catalyst regenerator vesselsis sequentially connected for regenerated catalyst discharge to aregenerated catalyst lift engager which has an outlet for regeneratedcatalyst flow to a liftpipe to convey regenerated catalyst to thecatalyst inlet of the reactor section.
 16. A method according to claim15 which includes means for selectively discharging regenerated catalystflow from each of the plurality of catalyst regenerator vessels insequence to the regenerated catalyst lift engager.
 17. A methodaccording to claim 13 in which the spent catalyst outlet of the reactorsection is connected for spent catalyst flow to a spent catalyst liftengager which has a spent catalyst outlet connected for spent catalystflow to a liftpipe to convey spent catalyst to a spent catalyst flowdistributor for directing spent catalyst sequentially to each of thecatalyst regenerator vessels.
 18. A method according to claim 11 inwhich the fixed bed catalytic reforming unit is a cyclic reforming unitincluding a regeneration circuit which is incorporated into theconverted unit to direct catalyst regeneration gas through the catalystin the regeneration vessel during the regeneration step.
 19. A methodaccording to claim 18 in which the catalyst regeneration gas directedthrough the catalyst includes a sequence of purge gas, oxidative gas toremove coke from the catalyst and halogen-containing gas for catalystrejuvenation.
 20. A method according to claim 13 in which the movingbed, continuous reforming reactor section comprises a plurality ofreforming reactors in a vertically stacked configuration and thecatalyst regeneration section comprises a plurality of catalystregeneration vessels converted from the fixed bed reactors of the fixedbed reforming unit.